Pulp-digester for paper-making



(No Model.)

RUGEN BARON RITTER 8v CHARLES KBLLNER.

PULP DIGESTER POR PAPER MAKING. No. 329,217'. ,f Patented Oct. 27,1885.

v i UNITED l STATES PATENT CEEicE.

EUGENBARON RITTER AND CHARLES KELLNER, OE GCERZ, AUSTRIA-HUN- GARY, ASSIGNORS TO WILLIAM A. RUSSELL, TRUSTEE, OE LAWRENCE,

MASS ACHUSETTS.

PULP-Dle'sTER FOR PAPER-MAKING.

SPECIFICATION forming part of Letters Patent No. 329,217, dated October 27, 1885.

, Application tiled May 27, 1885. Serial No. 166,836.k (No model.)

To all whom, it may concern:

Beit known that we, EUGEN BARON RITTER and CHARLEs KELLNER, subjects of the Emperor of Austria-Hungary, and residents of Goerz, a city in the Empire of Austria-Hungary, have invented certain new and useful Improvements in Linings of Pulp-Digesters for the Manufacture of Wood Pulp or Cellulose or other Fibrous Materials for Paper-Making,

ro of which the following is a specification.

Our invention relates principally to boilers or vessels employed for the treatment of fibrous materials or the manufacture of pulp for papermaking, and which are lined with a soft metal or lead; but our said invention is also applicable to lead-lined vessels for other purposes. Considerable difficulty has hitherto been eX- perieuced in keeping the lead in its relative position to the casing of iron or steel when 2o the digester is submitted tohigh temperatures.

The repeated action of heat causes it to continually increase in area, and thus to gradually accumulate into ridges and creases, which become brittle and break, necessitating` the `z 5 relining of the digester.

The object of our invention is to render the lead lining of digesters or vessels durable by providing an arrangement for securing the lead lining to the casing of the boiler orvessel 3o in such a manner that the creeping or sliding effect of the soft metal or lead lining is localized into sufficiently small portions to make the soft metal or lead lining much more durable for digesters. According to our invention We accomplish this by beveling ofi" each sheet all around Where they butt against each other, and are riveted to the outside coveringplates at an angle of about forty-five degrees (more or less) toward the outside of the shell,

4o and instead of batting the sheets together leave them apart to an amount about double the thickness of the plate of which the outside shell is composed. This is done on all seams both longitudinal and circumferential, leaving in this manner between all the sheets a space with the shape of what is called a dovetaiL The boiler nished in this manner by the boiler-maker is now treated as follows: It is placed in a horizontal position and the dovetail spaces covered with common sol- 5o dering solution, chloride of zinc, or chlorideof-zinc ammonium; or said space is tinned. The space is now heated either by fire on the outside or the blow-pipe on the inside till the space is so hot that, touched with a lead stick, the latter will melt. Melted hard lead is now cast into the so prepared space, which on cooling slowly is found to be soldered to the iron or steel of the sheets. The rivets of the joints are by the soldering well protected. 6o The lead is scraped or filed off level with the inside of the plates of tliedigester, and to this hard lead the lead or soft-metal plate forming the lining, cut in sheets a little larger than the hard-metal plates, is fastened by soldering- 6 5 and the spaces left between the several sheets are owed full with lead solder. ln this inanner the whole of the inside of the boiler is lined, and, if found necessary, the lead plate may be fastened to the hard-metal shell by ad- 7o ditional hard-lead rivets suitably spaced apart.

Ve will now proceed to describe our invention with the assistance of the accompanying drawings, which form part of this speciiication, in which- Figure l is a longitudinal section of part of one end of a digester; Fig. 2, part of a transverse section on the line X Y, Fig. l. Eig. 3 shows part of our invention on an enlarged scale. Fig. -lshows our invention applied to 8o a different form of digester to that shown in Fig. 1.

A A A2 are different sheets of the digcster.

B B are cover-plates, to which the several sheets composing the shell are riveted. 'C C 85 are longitudinal cover-plates. D is the inside lead or soft-metal lining. E are the dovetail spaces left between the several sheets composing the digester on the one side, and the covering-straps to which the several sheets 9o.

are riveted on the other side, filled with hard lead. E E', Fig. 3, show the places of soldering the inside lead-lining sheets, D D, to the hard-lead filling in the space E. F is the lead solder lilling the space left between the lead sheet-s. G shows hard-lead rivets.

Our invention may also be applied where flanged joints occur in digesters, as shown at Fig. 4. Between the iianges H His placed the hard-1ead ring J, to which the adjoining sheets D D are joined by autogenous soldering, so called burning Having now fully described our invention and the manner in which the same may be used or carried into effect, we would observe, in conclusion, that what we consider to be novel and original, and therefore claim as the invention, is

1. The combination, in a digester for treating brous materials, of the circumferential and longitudinal spaces E E E, left between the several plates composing the hard-metal shell of same, the edges of which are beveled so as to form a dovetail groove, as shown, D D, J[he soft-metal lining-plates secured to E January, 1885.

, EUGEN BARON RITTER.

CHARLES KELLNER. Witnesses:

GEORG MARTIN, J oHANN LUTTMANN. 

